There are various supplying method of a processing solution for a photographic light-sensitive material.
In photographic processing carried out with an automatic processor to develop, fix and bleach the light-sensitive material, a specific amount of processing agents is supplied as replenishers to the processor to compensate loss of the processing solution caused by being taken out together with the light-sensitive material to be processed or by being evaporated, oxidized or deteriorated. Such replenishers are generally sold in the form of concentrated solutions to be diluted with water when used.
However, undesirable problems sometimes arise in the method where such concentrated solutions are diluted. To be concrete, when a light-sensitive material is processed with a developer containing a conventional polyhydroxy benzene type developing agent, problems do not arise as long as processing is carried out at normal intervals, but when processing leaves a processing solution unreplenished at long intervals, the solution allows air oxidation to proceed, resulting in deteriorating the developer's activity and thereby lowering the photographic sensitivity. For example, when a light-sensitive material is processed, the operation of the automatic developer is closed at night and a light-sensitive material of the same kind is processed on the following morning, the sensitivity of the latter light-sensitive material fluctuates much more than that of the former light-sensitive material. In such a case, the activity of the developer must be restored by supplying a large amount of developer replenisher and, as a result, the efficiency of operation is lowered to a large extent. Further, in a recent processing system which uses a replenisher in a small amount for minimizing the amount of photographic waste liquor in view of environmental protection, a processing solution in running state is low in activity because of a small replenishing amount, while the tolerance for deterioration in developer activity has become very small owing to shortening of developing time brought about by the recent tendency toward more rapid developing. To cope with such a problem, there have so far been made various attempts such as thinning of a light-sensitive material by decreasing the binder amount used in a light-sensitive material, minimization of deterioration in developing activity by lessening the amount of silver halide contained in a light-sensitive material, and raise of developing temperature. However, these attempts are not effective enough to solve the problem, and the lowering in photographic sensitivity becomes intensified in photographic operation. In addition, disposal of waste processing solutions becomes difficult because of organic solvents contained therein; therefore, decrease in amount of organic solvents, particularly ethylene glycols (DEG, TEG, etc.) generally contained in a processing solution is strongly demanded.
Further, there are developed in recent years high contrast light-sensitive materials for use in printing by incorporating a contrast improver such as a hydrazine compound in light-sensitive emulsions. These light-sensitive materials have an advantage of being processed with a highly preservative developer having a sodium sulfite content larger than that of a lith developer, so that the use of a lith developer of poor preservability can be avoided. However, such light-sensitive materials are highly sensitive to a small fluctuation in developer's activity; therefore, to say nothing of the foregoing problems, these are liable to cause troubles such as sharpness or pepper spots when subjected to continuous processing (to be in running state).
Fixers, though not so susceptible as developers, have similar problems and, when left unused for a long time in an automatic processor, they are deteriorated in fixing capability and hardening capability. In fact, troubles such as fixing failure and hardening failure are often found in the recent rapid processing carried out at low replenishing rates using automatic processors.